Steam generator



Oct. 20, 1942. w. H. RICHARDS STEAM GENERATOR Filed 001?. 8, 1940 FIG. 2.

Patented Oct. 20, 1942 STAT PATENT OFFICE.

STEAM GENERATOR William H. Richards, Dayton, Ohio Application October 8, 1940,, Serial No. 360,311

((31. 122-40) (Granted under the act of March 3, 1883, as

7: Claim amended' April 30, 19

The invention described herein maybe manulac-tured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to, vapor generators. and moreparticularly to steam generators of the flash ype.

It is an object of my invention to provide ahot plate member as apart of the generator, separate and non-rigidly connected to the main structure, to thereby avoid the introduction of stresses. and the consequentwarping of the main structure due. tov expansion and contraction of thehot. plate member.

Itis a further object of my invention to provide in a. device of the character, described means coacting with said member for regulating the flow of liquid to said boiler as a function of the temperature of said hot plate member.

Other objects, advantages and novel details, of construction of my invention will be apparent from the following description and the accompanying drawing wherein like reference numerals indicate like, parts. throughout the several views and wherein:

Fig. 1 is, a vertical section view with parts in elevation showing my invention with thevalve in the open position;

Fig. 2. is a fragmentary section view showing thevalve in the closed position;

Fig. his a sectional view taken on the lines 33 OfFig. 1-

Referring to they drawing it will be seen that my novel steam generator comprises, as illustrated, a. casing a. chamber I 4; a burner l6 disposed below the casing head 2; a heat absorbing and dissipating elementor hot plate member I8 centrally disposed in the bottom head l2; and a thermo-responsive valve control. mechanism more fully hereinafter described. The burner- 16 is of the conventional gasjet type mounted on a base 28 and having a connection 2| With a source of gas.

The casing II] is. provided at the top with an outlet opening 22 for the steam generated, and with. apertures 24 at the bottom for access of the as connection, and air, to the burner. The bottom head [-2 is secured by means of screws to the casing at a point intermediate its ends to provide suitable space for the burner. The head [2 is; provided with a central opening 26 having immediately surrounding the same an internally presenting annular boss 23. The head also has an: upwardly extending skirt portion 30 to assist in providing a sealed fit with the casing.

As illustrated, there is an upwardly extending spider 32 integrally constructed with the skirt portion 38.. The. spider supports a valve housing 34 made in two parts 36 and 38 threadedly connected for convenience of construction and as- [Q and a bottom head I 2 forming sembly. Part 36: may be. constructed integrally with the, spider 32, as shown. Part38 hasa bore it] for receiving a conduit 42 connected through the casing It to a. source of water or other liquid. A second bore 44 is formed in the part 38 to provide a recess in communication with the conduit 42, and providing a valve seat 46 in Which is disposed a ball check 43. The upper end of the bore is sealed with a plug 52] which also, serves as an abutmentfor a spring 52 for actuating ball 48 against the seat Part 3.5 has a recess formed therein and. cooperates with part 38 to form a chamber 54. from which water may spray or drop through orifices 55 in the bottom of part 38 on to. the hot plate I 8.

The. heat. absorbing and dissipating or heatexchange element [3 is made of some material having the property of relatively high heat conductivity, such as copper or aluminum, whereas the base or bottom head [2 is. made preferably of iron or somev alloy having a relatively low heat conduction property. The element I8 is. formed of two parts 58. and 66 adapted to be threadedly connected, as illustrated, to enable assembly. Part 58. is provided with a head portion 62 of suflicient diameter to rest on the annular boss 28 and a shank portion 64 of a diameter to be received in the bore 26 in the bottom head I2 and havesunicient space margin to accommodate the maximum expansion to. be encountered. It will thus be seen that the element I8 seats on the annular boss 28 in loosely mounted relation and is axially movable in guided relation to said bottom head. The internal pressure generated by the steam in the chamber l4 assists gravity in causing the head portion 62 to, firmly seat and seal the opening 26.

Means are provided to coact with the hot plate member [8 to control the flow of liquid through valve seat 43. For this purpose, I preferably use a thermo rod 66 made of a material readily expansible and contractible with heat. The rod is in the form of an extension portion of element. [8 and is connected thereto as by a pressed or forced fit in a bore 68 in the head of element is. The rod 66 extends through a guiding bore iii in the part 36 and is adapted when expanded to engage the ball check 48. The thermo rod is of such a length that the top, when cold, is spaced from the ball 48 a distance sufiicient to accommodate the expansion of the rod which occurs before the plate I 8 attains the desired operating temperature, and to also allow for any creeping of the metal, or other lengthening, due to time and age. It is to be noted that the recess 44 formed in the upper valve housing part 38 allows for a greater displacement of the ball check 48 than will be required to accommodate the maximum expansion of the thermo rod in order to avoid putting the rod under compression, which would cause buckling.

Upon the application of heat to the element I8 the thermo rod expands, and when the desired hot plate temperature, or a little in excess, is attained, the rod engages the ball check and unseats same. Water then flows through conduit 42, valve seat 46, chamber 54, and orifices 56 on to the head portion 62 of element I8. The water is converted to steam in the conventional flash manner. If the water flows at a rate faster than that in which it is in equilibrium with the temperature of the head portion 62, the element I8 and the thermo rod will be cooled and the thermo rod will contract, allowing the ball check to close off the water until the heat has accumulated in element I8 in sufficient quantity to cause the thermo rod to expand. If the temperature of element I8 increases to a point where it exceeds the temperature at which the head portion 62 is in equilibrium with the water supply, then the thermo rod further expands allowing a still larger quantity of water to enter to establish equilibrium.

One modification of the design of the thermo 9 rod is to construct it as a piece separate from either the ball check or the element I8, but disposed between these two elements in the guiding bore 10 and in contact with element I8. The design may also be varied by fixedly connecting the thermo rod to both the ball check and the element I8, in which case the actuating spring 52 for the ball check may be omitted. In this case, the thermo rod is constructed of a length designed so that the ball check will seat in the valve seat while the apparatus is cold. The element I8 is preferably not quite seated on the annular boss by a spacing suflicient to accommodate the expansion of the rod which occurs before the plate I8 attains the When the rod is fixedly connected to both element I8 and ball check, no harm will arise from the failure of element I8 to seat on the annular boss as the element I8 then acts as a Weight urging the ball check into seating engagement and preventing the flow of water into chamber I4.

It is to be understood that my invention is not limited to the form illustrated and described herein, but that it includes such modifications and equivalents as may be included within the scope of the appended claims.

I claim: a

1. In a device of the class described, a compartment having a support, a heat absorbing and dissipating member vertically supported by said support and disposed partly within and partly without said compartment in loosely fitting but substantially fluid sealed relation to said support, means for delivering liquid from a source and for directing same on said member interiorly of said compartment including valve control means, and an expansible and contractible element responsive to the temperature of said memer in operative association with said valve control means for regulating the amount of liquid directed on to said member.

2. In a steam generating device, a support, a heat exchange member adapted to be heated loosely mounted on said support in guided relation thereto and seating thereon, a valve housing fixedly spaced from said support and adapted to be communicatively connected to a source of water, said valve housing including a seat and a desired operating temperature.

valve control member operatively disposed in said seat, means for discharging water from .said valve housing on to said member, and means operatively connected to said control member for controlling the flow of water through said seat as a function of the temperature of said first-mentioned member.

3. In a flash boiler, a valve for regulating the amount of water supplied to said boiler, a support, a heat exchange member adapted to be heated mounted in said support so as to be free to expand and contract relative'to said support with ,change in temperature of said member, said member having an extension portion made of a material having a relatively high coefficient of expansion, said extension portion being responsive to the temperature of said member and being arrangedto control said valve as a function of the expansion and contraction thereof.

4. A flash boiler having a member adapted to be heated, said member being loosely mounted in said boiler, means for communication with a source of liquid, spray means operatively communicatively coupled to said first-mentioned means for spraying a liquid on said heated memher, and means for controlling the amount of liquid sprayed on said member in accordance with the temperature of said member, said means comprising a valve housing having a seat therein and a ball check Valve disposed in said seat, a thermo-responsive expansible and contractible element guidably disposed between said ball check valve and said member for controlling the flow of liquid through said seat as a function of the temperature of said member.

5. A flash boiler having a base with an opening therein, a plug element disposed in said opening so as to be exposable to a source or heat and seating in said opening, said element being made of a metal having a greater heat conductivity than the material of which said base in constructed, means for supplying water to said boiler, valve means in said Water supply means and a thermoresponsive expansible and contractible element in contactual relation with said plug element for controlling said Valve for regulating the 'amount of water supplied to said boiler in accordance with the temperature of said element. a

6. A flash boiler having an opening in the base thereof, a heat transfer member mounted for sliding movement in said opening and seating therewith, means for discharging water on to said element, valve means for controlling the amount of water discharged in accordance with the temperature of said member, said valve means including a housing fixedly spaced from said support, a valve seat in said housing, a ball check adapted to engage said seat, and a thermoresponsive expansible and contractible element adapted to abut said ball check at one end and in contactual relation at the other end to said heat transfer member.

'7. In a fiash boiler, a vaporizing chamber, heating means, a support base separating said vaporizing chamber and said heating means and having an opening therein, a heat-exchange element loosely mounted in said opening and sealingly supported by said base member, means for sup plying liquid to be vaporized to said vaporizing chamber and said heat-exchange element, "and means for regulating the flow of such liquid.

WILLIAM H. RICHARDS.- 

